Blow-molded unitary structure with enhanced strength

ABSTRACT

A blow-molded unitary structure includes a panel having first and second panel walls and a generally hollow interior between the first and second panel walls. The structure also includes one or more different types of strengthening elements monolithically formed with the panel and across a substantial portion of the panel to enhance the strength of the structure. A strengthening element can be a depression recessing from the second panel wall toward an interior of the panel, a protrusion protruding from the second panel wall toward an exterior of the panel, a rib protruding outwardly toward the exterior of the panel and a trench formed by side walls of adjacent protrusions.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Chinese Utility ModelApplications CN 202021507901.7 filed Jul. 27, 2020, CN 202021508027.9filed Jul. 27, 2020, CN 202021508934.3 filed Jul. 27, 2020, andCN202121253741.2 filed Jun. 2, 2021. The disclosure of each applicationis incorporated herein for all purposes by reference in its entirety.

FIELD OF THE INVENTION

The present invention generally relates to blow-molded structures and,in particular, to blow-molded unitary structures with enhanced strength.

BACKGROUND

Some existing tabletops are made by blow molding plastics. Suchtabletops are usually hollow structures with insufficient strength. Inuse or during transportation, they can be easily bent and deformed.

Given the current state of the art, there remains a need for blow-moldedstructures that address the abovementioned issues.

The information disclosed in this Background section is provided for anunderstanding of the general background of the invention and is not anacknowledgement or suggestion that this information forms part of theprior art already known to a person skilled in the art.

SUMMARY OF THE INVENTION

The present disclosure provides blow-molded unitary structures withenhanced strength. The structures can be used, for instance, as atabletop, a benchtop, a countertop, a bed panel, or the like.

In various exemplary embodiments, the present disclosure provides ablow-molded unitary structure including a panel, a plurality ofdepressions, and a plurality of protrusions. The panel includes a firstpanel wall and a second panel wall spaced apart from the first panelwall. The plurality of depressions is monolithically formed with thepanel, each recessing from the second panel wall toward an interior ofthe panel. Each depression in the plurality of depressions includes anopen depression top at the second panel wall, a closed depression bottomopposite to the open depression top, and a depression side wallconnecting the open depression top and the closed depression bottom. Theplurality of protrusions is also monolithically formed with the panel,each protruding from the second panel wall toward an exterior of thepanel. Each protrusion in the plurality of protrusions includes an openprotrusion base at the second panel wall, and a closed protrusion coversurrounding the open protrusion base. Depressions in at least a subsetof the plurality of depressions are arranged alternately withprotrusions in at least a subset of the plurality of protrusions acrossat least a portion of the panel. The plurality of depressions and theplurality of protrusions collectively enhance a strength of theblow-molded unitary structure.

In some exemplary embodiments, the blow-molded unitary structure furtherincludes a plurality of ribs monolithically formed with the panel. Eachrespective rib in the plurality of ribs protrudes outwardly toward theexterior of the panel, and each respective rib in at least a subset ofthe plurality of ribs connects corresponding adjacent protrusions in theplurality of protrusions.

In some exemplary embodiments, the second panel wall is substantiallyparallel to the first panel wall.

In an exemplary embodiment, a depression is separated from its adjacentdepression in the plurality of depressions by a distance that is fromabout 3 to about 7 (e.g., about 3, 4, 5, 6 or 7) times a thickness ofthe structure.

In some exemplary embodiments, the closed depression bottom is formedmonolithically at the first panel wall or is a part of the first panelwall.

In an exemplary embodiment, the subset of the plurality of depressionsand the subset of the plurality of protrusions are arrangedsubstantially uniformly across the portion of the panel.

In an exemplary embodiment, the plurality of depressions and theplurality of protrusions are arranged substantially across the panel.

In some exemplary embodiments, the closed protrusion cover of eachprotrusion in at least a subset of the plurality of protrusions issubstantially rounded.

In some exemplary embodiments, the closed protrusion cover of eachprotrusion in at least a subset of the plurality of protrusions includesa top and a side wall connecting the top with the open protrusion baseof each respective protrusion.

In some exemplary embodiments, the top of the closed protrusion cover isarched or dome-shaped.

In an exemplary embodiment, an edge between the top and side wall of theclosed protrusion cover is arched.

In some exemplary embodiments, the top of the closed protrusion cover issubstantially planar and parallel to the second panel wall.

In some exemplary embodiments, a trench is formed between the side wallsof adjacent protrusions in the subset of the plurality of protrusions.

In some exemplary embodiments, the trench connects two depressionsadjacent to the side walls.

In an exemplary embodiment, the trench has a width that is substantiallyequal to or less than a width of any one of the two depressions.

In various exemplary embodiments, the present disclosure provides ablow-molded unitary structure including a panel, a plurality ofdepressions and a plurality of protrusions. The panel includes a firstpanel wall and a second panel wall spaced apart from the first panelwall. The plurality of depressions is monolithically formed with thepanel, each recessing from the second panel wall toward an interior ofthe panel. The plurality of protrusions is also monolithically formedwith the panel, each protruding from the second panel wall toward anexterior of the panel. Each protrusion in the plurality of protrusionsincludes an open protrusion base at the second panel wall, and a closedprotrusion cover surrounding the open protrusion base. The closedprotrusion cover of each protrusion in at least a subset of theplurality of protrusions includes a substantially planar top and a sidewall connecting the substantially planar top with the open protrusionbase of each respective protrusion. A trench is formed between the sidewalls of adjacent protrusions in the subset of the plurality ofprotrusions, and connects two depressions adjacent to the side walls.

In some exemplary embodiments, the trench has a width that issubstantially equal to or less than a width of any one of the twodepressions.

In various exemplary embodiments, the present disclosure provides ablow-molded unitary structure including a panel, a plurality ofdepressions, a plurality of protrusions, and a plurality of ribs. Thepanel includes a first panel wall and a second panel wall spaced apartfrom the first panel wall. The plurality of depressions ismonolithically formed with the panel, each recessing from the secondpanel wall toward an interior of the panel. The plurality of protrusionsis also monolithically formed with the panel, each protruding from thesecond panel wall toward an exterior of the panel. Each protrusion inthe plurality of protrusions includes an open protrusion base at thesecond panel wall, and a closed protrusion cover surrounding the openprotrusion base. The plurality of ribs is also monolithically formedwith the panel, each protruding outwardly toward the exterior of thepanel. Each respective rib in at least a subset of the plurality of ribsconnects corresponding adjacent protrusions in the plurality ofprotrusions.

In some exemplary embodiments, the closed protrusion cover of eachprotrusion in at least a subset of the plurality of protrusions includesan arched or dome-shaped top and a side wall connecting the arched ordome-shaped top with the open protrusion base of each respectiveprotrusion.

In an exemplary embodiment, an edge between the arched or dome-shapedtop and side wall of the closed protrusion cover is arched.

In various exemplary embodiments, the present disclosure provides ablow-molded unitary structure including a panel, a plurality of firstdepressions, a plurality of first protrusions, and a plurality of secondprotrusions. The panel includes a first panel wall and a second panelwall spaced apart from the first panel wall. The plurality of firstprotrusions monolithically formed with the panel, each protruding fromthe second panel wall toward an exterior of the panel and elongated inthe first direction. The plurality of second protrusions ismonolithically formed with the panel, each protruding from the secondpanel wall toward an exterior of the panel and elongated in the seconddirection. At least a subset of the plurality of first depressions isarranged into a plurality of depression rows in a first direction and aplurality of depression columns in a second direction across at least aportion of the panel. Moreover, first protrusions in at least a subsetof the plurality of first protrusions are arranged alternatively withdepression rows in at least a subset of the plurality of depressionrows. Second protrusions in at least a subset of the plurality of secondprotrusions are arranged alternatively with depression columns in atleast a subset of the plurality of depression columns. Further, thefirst protrusions in the subset of the plurality of first protrusionsand the second protrusions in the subset of the plurality of secondprotrusions cross each other. The plurality of first depressions, theplurality of first protrusions, and the plurality of second protrusionscollectively enhance a strength of the blow-molded unitary structure.

In some exemplary embodiments, the blow-molded unitary structure furtherincludes a plurality of reinforcement members, each monolithicallyformed at a first depression in the plurality of first depressions.

In an exemplary embodiment, the number of reinforcement members is thesame as the number of first depressions, and one reinforcement is formedat each first depression in the plurality of first depressions.

In some exemplary embodiments, each reinforcement member in theplurality of reinforcement members is formed at a depression bottom of acorresponding first depression in the plurality of first depressions.

In an exemplary embodiment, each reinforcement member in the pluralityof reinforcement members is recessed from the depression bottom of thecorresponding first depression in the plurality of first depressionstowards the first panel wall.

In some exemplary embodiments, the reinforcement member includes aplurality of reinforcement elements connected with each other at theirends.

In an exemplary embodiment, a first protrusion in the plurality of firstprotrusions and a second protrusion in the plurality of secondprotrusions have different heights.

In some exemplary embodiments, a height of a first protrusion in theplurality of first protrusions or a second protrusion in the pluralityof second protrusions is about 1/7 to about ⅘ of a distance between twoadjacent first depressions, about ⅙ to about ¾ of the distance betweentwo adjacent first depressions, or about ⅕ to about ⅔ of the distancebetween two adjacent first depressions. In an exemplary embodiment, thedistance between two adjacent first depressions is measured from acenter of one first depression to a center of the other firstdepression.

In some exemplary embodiments, a width of a first protrusion in theplurality of first protrusions or a second protrusion in the pluralityof second protrusions is about 1/7 to about ½ of a distance between twoadjacent first depressions, about ⅙ to about ⅖ of the distance betweentwo adjacent first depressions, or about ⅕ to about ⅓ of the distancebetween two adjacent first depressions. In an exemplary embodiment, thedistance between two adjacent first depressions is measured from acenter of one first depression to a center of the other firstdepression.

In some exemplary embodiments, a first depression in the plurality ofdepression rows or in the plurality of depression columns is surroundedby a transition member that connects the first depression with adjacentfirst and second protrusions. In an exemplary embodiment, the transitionmember comprises a first step and a second step.

In some exemplary embodiments, the blow-molded unitary structure furthercomprises a second depression monolithically formed with the panel andrecessing from the second panel wall toward the interior of the panel.The second depression is curvy and disposed along one or more edges ofthe panel. In an exemplary embodiment, the second depression has asubstantially wave shape.

In some exemplary embodiments, a first protrusion in the plurality offirst protrusions or a second protrusion in the plurality of secondprotrusion has a tunnel shape.

The structures of the present disclosure have other features andadvantages that will be apparent from, or are set forth in more detailin, the accompanying drawings, which are incorporated herein, and thefollowing Detailed Description, which together serve to explain certainprinciples of exemplary embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and constitute apart of this specification, illustrate one or more exemplary embodimentsof the present disclosure and, together with the Detailed Description,serve to explain the principles and implementations of exemplaryembodiments of the invention.

FIG. 1 is a bottom view illustrating an exemplary structure inaccordance with some exemplary embodiments of the present disclosure.

FIG. 2 is a schematic cross-sectional view taken along line A-A of FIG.1.

FIG. 3 is a schematic cross-sectional view taken along line B-B of FIG.1.

FIG. 4 is a bottom view illustrating the exemplary structure of FIG. 1.

FIG. 5 is a schematic cross-sectional view taken along line C-C of FIG.4.

FIG. 6 is a bottom view illustrating an exemplary structure inaccordance with some exemplary embodiments of the present disclosure.

FIG. 7 is a schematic cross-sectional view taken along line A-A of FIG.6.

FIG. 8 is a schematic cross-sectional view taken along line B-B of FIG.6.

FIG. 9 is a bottom view illustrating the exemplary structure of FIG. 6.

FIG. 10 is a schematic cross-sectional view taken along line C-C of FIG.9.

FIG. 11 is a bottom perspective view illustrating an exemplary structurein accordance with some exemplary embodiments of the present disclosure.

FIG. 12 is a bottom view illustrating the exemplary structure of FIG.11.

FIG. 13 is a schematic cross-sectional view taken along line A-A of FIG.11.

FIG. 14 is a schematic cross-sectional view taken along line B-B of FIG.11.

FIG. 15 is a schematic cross-sectional view taken along line C-C of FIG.11.

FIG. 16 is a bottom view illustrating an exemplary structure inaccordance with some exemplary embodiments of the present disclosure.

FIG. 17 is a schematic cross-sectional view taken along line E-E of FIG.16.

FIG. 18 is an enlarged view taken along circle F of FIG. 16.

FIG. 19 is a partially enlarged view of FIG. 16.

As will be apparent to those of skill in the art, the componentsillustrated in the figures described above are combinable in any usefulnumber and combination. The figures are intended to be illustrative innature and are not limiting.

DETAILED DESCRIPTION

Reference will now be made in detail to implementations of exemplaryembodiments of the present disclosure as illustrated in the accompanyingdrawings. The same reference indicators will be used throughout thedrawings and the following detailed description to refer to the same orlike parts. Those of ordinary skill in the art will understand that thefollowing detailed description is illustrative only and is not intendedto be in any way limiting. Other embodiments of the present disclosurewill readily suggest themselves to such skilled persons having benefitof this disclosure.

In the interest of clarity, not all of the routine features of theimplementations described herein are shown and described. It will beappreciated that, in the development of any such actual implementation,numerous implementation-specific decisions are made in order to achievethe developer's specific goals, such as compliance with application- andbusiness-related constraints, and that these specific goals will varyfrom one implementation to another and from one developer to another.Moreover, it will be appreciated that such a development effort might becomplex and time-consuming, but would nevertheless be a routineundertaking of engineering for those of ordinary skill in the art havingthe benefit of this disclosure.

Many modifications and variations of the exemplary embodiments set forthin this disclosure can be made without departing from the spirit andscope of the exemplary embodiments, as will be apparent to those skilledin the art. The specific exemplary embodiments described herein areoffered by way of example only, and the disclosure is to be limited onlyby the terms of the appended claims, along with the full scope ofequivalents to which such claims are entitled.

Embodiments of the present disclosure are described in the context ofstructures with enhanced strength. An exemplary structure of the presentinvention is a unitary piece formed by blow molding plastics such ashigh density polyethylene (HDPE), low density polyethylene (LDPE),polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate(PET), thermoplastic elastomers (TPE), or the like. An exemplarystructure of the present disclosure can be used, for instance, as atabletop, a benchtop, a countertop, a bed panel, or the like.

A structure of the present disclosure generally includes a panel havingtwo or more panel walls and a generally hollow interior formed betweenthe panel walls. The panel can be of various regular or irregularshapes, including but not limited to a square shape, a round shape or arectangular shape.

A structure of the present disclosure also includes one or moredifferent types of strengthening elements monolithically formed with thepanel, thereby creating a unitary one-piece structure with enhancedstrength. Strengthening elements include, but are not limited to, aplurality of depressions, a plurality of protrusions, a plurality ofribs, a plurality of trenches, or any combination thereof. In someexemplary embodiments, the strengthening elements are distributed acrossat least a portion of the panel. The strengthening elements enhance thestrength of the structure (e.g., increases rigidity of the structure)and prevent the structure from bending, warping or deforming.

The strengthening elements (e.g., depressions, protrusions, ribs, ortrenches) can have any suitable shapes, sizes or orientations. Forinstance, a depression can have a regular (e.g., rectangular, square,circular, oblong or the like) or irregular shape. In addition, adjacentdepressions can have the same configuration or different configurations.In some exemplary embodiments, a depression includes a stepwise sidewall configured to increase the strength of the depression andaccordingly to increase the strength of the panel and/or structure.Similarly, a protrusion/rib/trench can have a regular or irregularshape, and adjacent protrusions/ribs/trenches can have the sameconfiguration or different configurations.

The depressions, protrusions, ribs, and/or trenches can be formed at anysuitable positions independent from each other or related to each other.For instance, a protrusion can be formed at a position adjacent to noneof the plurality of depressions, or at a position adjacent to 1, 2 ormore than 2 depressions. Likewise, a depression can be formed at aposition adjacent to none of the plurality of protrusions, or at aposition adjacent to 1, 2 or more than 2 protrusions. The depressions,protrusions, ribs, and/or trenches can be arranged uniformly ornonuniformly across the panel. In some exemplary embodiments,depressions in at least a subset of the plurality of depressions arearranged alternately with protrusions in at least a subset of theplurality of protrusions across at least a portion of the panel. In someexemplary embodiments, the plurality of depressions and the plurality ofprotrusions are arranged substantially uniformly across the panel.

Referring now to FIGS. 1-5, there is depicted exemplary structure 100 inaccordance with some exemplary embodiments of the present disclosure. Asshown, structure 100 includes a panel such as panel 110. The panelusually includes multiple walls and a generally hollow interior. Forinstance, in some exemplary embodiments, panel 110 includes first panelwall 111, second panel wall 112 and generally hollow interior 113. Firstpanel wall 111 and second panel wall 112 are spaced apart from eachother (e.g., in the vertical direction of FIG. 2), creating generallyhollow interior 113 in between.

The first and second wall panels can be, but do not have to be,completely spaced apart from each other. For instance, in some exemplaryembodiments, the first and second wall panels can be joined with eachother at one or more locations. Similarly, the generally hollow interiorcan be completely hollow or partially hollow with one or more structuresformed or disposed within. Additionally, the first and second panelwalls each can be planar or nonplanar. For instance, in an exemplaryembodiment, each of the first and second panel walls is substantiallyplanar, and the first and second panel walls are substantially parallelto each other. In another exemplary embodiment, at least a portion ofthe first or second panel wall is curved.

The first and second panel walls can have the same thickness ordifferent thicknesses. By way of example, FIG. 2 illustrates the firstand second panel walls having substantially the same thickness indicatedby h. In some exemplary embodiments, a distance separating the first andsecond panel walls is about 2, 3, 4, 5, or more than about 5 times athickness of the first or second panel wall. In an exemplary embodiment,the distance separating the first and second panel walls is from about 4to about 7 (e.g., about 4, 5, 6, or 7) times a thickness of the first orsecond panel wall.

In some exemplary embodiments, structure 100 includes a plurality ofdepressions, such as depression 120, monolithically formed with thepanel and thus creates a unitary one-piece structure. Differentdepressions can be but do not have to be identical or substantially thesame as each other. For instance, different depressions can have thesame or different shapes or sizes, or can be arranged in the same ordifferent orientations. By way of example, FIGS. 1-5 illustrates theplurality of depressions 120 monolithically formed with the first orsecond panel wall, each recessing from the second panel wall toward theinterior of the panel (e.g., toward the first panel wall).

In some exemplary embodiments, depression 120 includes an open top suchas open top 121. Cross-sectional-wise, the open top can have anysuitable regular or irregular shapes, including but not limited topolygon (e.g. triangle, rectangle, square, diamond), circle, oblong,oval, or the like. Depression 120 also includes a closed bottom, such asclosed bottom 122, opposite to the open top. The closed bottom can becompletely separated from first panel wall 111 (e.g., there is a gapbetween the closed bottom and the first panel wall), or formed at thefirst panel wall (e.g., the closed bottom is part of the first panelwall), or anywhere in between. By way of example, FIG. 2 illustrates thedepression having the close bottom formed at the first panel wall andbeing part of the first panel wall. Depression 120 also includes adepression side wall such as depression side wall 130. The depressionside wall joins or connects the open top and close bottom of thedepression.

Depressions 120 can be distributed uniformly, generally uniformly, ornon-uniformly across at least a portion of the panel, in which adjacentdepressions are generally spaced apart from each other. For instance, insome exemplary embodiments, two adjacent protrusions 140 are spacedapart from each other, forming a gap, such as gap 125 or gap 126,between the edges or side walls of the two adjacent depressions. Gap 125and gap 126 can be the same as or different from each other. In someexemplary embodiments, at least some of the depressions are arranged ina pattern, which can be regular or irregular. For instance, some or allof the depressions are arranged to form row(s), column(s), circle(s) orthe like. In some exemplary embodiments, the open top has asubstantially square shape, and the plurality of depressions is arrangedin a pattern such that each edge of the substantially square shaped opentop is oriented at an angle with respect to an edge of the panel. Forinstance, in an exemplary embodiment, the plurality of depressions isarranged in a pattern such that each edge of the substantially squareshaped open top is oriented at substantially 45 degrees with respect toa side edge of the panel.

In some exemplary embodiments, adjacent depressions are separated by adistance greater than a thickness of the structure. For instance, in anexemplary embodiment, the distance separating two adjacent depressionsis more than about 2, more than about 3, or more than about 4 times thethickness of the structure. In another exemplary embodiment, thedistance separating two adjacent depressions is from about 3 to about 7(e.g., about 3, 4, 5, 6, or 7) times the thickness of structure. Instill another exemplary embodiment, the distance separating two adjacentdepressions is from about 3 to about 5 (e.g., about 3, 4, or 5) timesthe thickness of structure. The distance separating two adjacentdepressions can be measured from center-to-center or edge to edge of theadjacent depressions. For instance, “d1” and “d2” in FIG. 1 indicate thedistance separating adjacent depressions in a row or column,respectively, measured from center-to-center of the adjacentdepressions. “d3” in FIG. 4 indicates the distance separating diagonallyadjacent depressions measured from center-to-center of the adjacentdepressions. In some exemplary embodiments, the distance separating twoadjacent depressions measured from edge to edge of the adjacentdepressions equals substantially the length of the gap (e.g., gap 125 orgap 126) between the two adjacent depressions. The thickness of thestructure is generally measured from the first panel wall to the secondpanel wall, as illustrated by “t1” (e.g., from the exterior surface ofthe first panel wall to the exterior surface of the second panel wall),or from the first panel wall to the top of the closed protrusion cover,as illustrated by “t2” (e.g., from the exterior surface of the firstpanel wall to the exterior surface of the top of the closed protrusioncover) in FIG. 2.

As a non-limiting example, in an exemplary embodiment, the distanceseparating two adjacent depressions in a row or a column is about 47 mmor the like. The distance separating two diagonally adjacent depressionsis about 66 mm or the like. The length of the gap (e.g., the distanceseparating adjacent depressions measured from edge to edge of theadjacent depressions) is about 33 mm or the like. The thickness of thestructure measured from the first panel wall to the second panel wall isabout 9.5 mm or the like.

In some exemplary embodiments, structure 100 includes a plurality ofprotrusions, such as protrusion 140, monolithically formed with thepanel and thus creates a unitary one-piece structure. Differentprotrusions can be but do not have to be identical or substantially thesame as each other. For instance, different protrusions can have thesame or different shapes or sizes, or can be arranged in the same ordifferent orientations. By way of example, FIGS. 1-5 illustrates theplurality of protrusions 140 monolithically formed with the second panelwall, each protruding from the second panel wall toward an exterior ofthe panel (e.g., protruding in a direction opposite to the first panel).In a non-limiting exemplary embodiment, the height of a protrusion(e.g., the distance measured from the second panel to the top of theprotrusion) is about 3.5 mm or the like.

Like the depressions, protrusions 140 can be distributed uniformly,generally uniformly, or non-uniformly across at least a portion of thepanel. Protrusions 140 can be formed at any suitable positionsindependent from depressions 120 or related to depressions 120. Thenumber of the protrusions can the same as or different from the numberof depressions. For instance, in some exemplary embodiments, at leastsome protrusions (e.g., protrusions in at least a subset of theplurality of protrusions) are arranged alternately with some depressions(e.g., depressions in at least a subset of the plurality of depressions)across at least a portion of the panel. In an exemplary embodiment, allprotrusions are arranged alternately with the depressions. By way ofexample, FIGS. 1 and 4 illustrate the depressions and protrusionsdistributed uniformly across the panel and alternating with each other.

In some exemplary embodiments, adjacent protrusions are separated by adistance greater than a thickness of the structure. For instance, in anexemplary embodiment, the distance separating two adjacent protrusionsis more than about 2, more than about 3, or more than about 4 times thethickness of the structure. In another exemplary embodiment, thedistance separating two adjacent protrusions is from about 3 to about 7(e.g., about 3, 4, 5, 6, or 7) times the thickness of structure. Instill exemplary embodiment, the distance separating two adjacentprotrusions is from about 3 to about 5 (e.g., about 3, 4, or 5) timesthe thickness of structure. The distance separating two adjacentprotrusions can be measured from center-to-center or edge to edge of theadjacent protrusions. By way of example, FIG. 1 illustrates thedistance, d4, separating adjacent protrusions measured fromcenter-to-center of the adjacent protrusions. In some exemplaryembodiments, the distance separating two adjacent protrusions measuredfrom edge to edge of the adjacent protrusions equals substantially thewidth of the gap (e.g., gap 125 or gap 126) between the two adjacentprotrusions.

The distance separating adjacent protrusions can be the same as ordifferent from the distance separating adjacent depressions. In anexemplary embodiment where the depressions and protrusions are uniformlyand alternatively distributed, the distance separating adjacentprotrusions measured from center-to-center of the adjacent protrusionsis substantially the same as the distance separating adjacentdepressions measured from center-to-center of the adjacent depressionsalong the same direction (e.g., along the row or column direction).

In some exemplary embodiments, protrusion 140 includes an open base suchas open base 141. In an exemplary embodiment, the open base of aprotrusion is connected to hollow interior 113 formed between the firstand second panel walls. Cross-sectional-wise, the open base can have anysuitable regular or irregular shapes, including but not limited topolygon (e.g. triangle, rectangle, square, diamond), circle, oblong,oval, or the like.

Protrusion 140 also includes a closed cover, such as closed cover 142,that surrounds and covers the open protrusion base. The closedprotrusion cover of a protrusion can have any suitable regular orirregular shapes, including but not limited to substantially arched,rounded, dome, pointed or planar shapes. In some exemplary embodiments,for at least some protrusions, the closed protrusion cover includes atop and a side wall that surrounds the open protrusion base and connectsthe top with the open protrusion base.

For instance, by way of example, FIGS. 1-5 illustrate closed protrusioncover 142 includes a substantially arched or dome-shaped top, such astop 143, and a side wall, such as side wall 144, that surrounds the openprotrusion base and connects the top with the open protrusion base. Inan exemplary embodiment, an edge, such as edge 145, between the top andside wall of the closed protrusion cover is arched.

As another example, FIGS. 11-15 illustrate closed protrusion cover 142includes a substantially planar top, such as top 146, and a side wall,such as side wall 147, that surrounds the open protrusion base andconnects the top with the open protrusion base. In some exemplaryembodiments, top 146 is substantially parallel to the second panel wall.In an exemplary embodiment, for at least a subset of protrusions, top146 is substantially planar and parallel to the second panel wall. Theplanar tops collectively form (or are considered as) a third panel wallsuch as panel wall 114. In some exemplary embodiments, a trench, such astrench 148 is formed between the side walls of adjacent protrusions inthe subset of the plurality of protrusions. In an exemplary embodiment,the trench connects two adjacent depressions, e.g., extending from onedepression to another depression adjacent to the side walls of theprotrusions that form the trench. The trench has a width defined by adistance separating the two side walls of the protrusions. The width ofthe trench can be either greater than, equal to, or less than a width ofan adjacent depression.

In some exemplary embodiments, the structure includes additional,optional or alternative features. For instance, referring to FIGS. 6-10,in some exemplary embodiments, a structure of the present inventionincludes a plurality of ribs, such as rib 160, monolithically formedwith the panel and thus creates a unitary one-piece structure. Rib 160can have any suitable shape and size and can be oriented in any suitableorientation. Different ribs can be but do not have to be identical orsubstantially the same as each other. For instance, different ribs canhave the same or different shapes or sizes, or can be arranged in thesame or different orientations. By way of example, FIGS. 6-10illustrates the plurality of ribs 160 monolithically formed with thesecond panel wall and/or protrusions 140, each protruding outwardlytoward the exterior of the panel (e.g., protruding in a directionopposite to the first panel). In an exemplary embodiment, a rib is acrease, a ridge or the like formed at the second panel wall and/orprotrusion. In some exemplary embodiments, a rib extends from oneprotrusion, across a gap (e.g., gap 125 or gap 126), to anotherprotrusion. In a non-limiting exemplary embodiment, the height of a rib(e.g., the distance measured from the second panel to the top of therib) is about 3.5 mm or the like.

Referring now to FIGS. 16-19, there is depicted exemplary structure 200in accordance with some exemplary embodiments of the present disclosure.As shown, structure 200 includes a panel, such as panel 210. Like panel110, panel 210 usually includes multiple walls and a generally hollowinterior. For instance, in some exemplary embodiments, panel 210includes first panel wall 111, second panel wall 112 and generallyhollow interior 113. First panel wall 111 and second panel wall 112 arespaced apart from each other (e.g., in the vertical direction of FIG.17), creating generally hollow interior 113 in between.

In some exemplary embodiments, structure 200 includes a plurality offirst depressions, such as depression 220, monolithically formed withthe panel. Like depression 120, different depressions 220 can be but donot have to be identical or substantially the same as each other. Forinstance, different depressions 220 can have the same or differentshapes or sizes, or can be arranged in the same or differentorientations. By way of example, FIGS. 16 and 17 illustratesubstantially the same or identical depressions 220 monolithicallyformed with the second panel wall, each recessing from the second panelwall toward the interior of the panel (e.g., toward the first panelwall). Also, like depressions 120, depressions 220 can be distributeduniformly, generally uniformly, or non-uniformly across at least aportion of the panel, in which adjacent depressions are generally spacedapart from each other.

In some exemplary embodiments, at least of a subset of the plurality offirst depressions is arranged into a plurality of depression rows in afirst direction (e.g., x-direction in FIG. 16) and a plurality ofdepression columns in a second direction (e.g., y-direction in FIG. 16)across at least a portion of the panel. Distances between differentadjacent depression rows can be the same or different. Similarly,distances between different adjacent depression columns can be the sameor different. In addition, a distance between adjacent depression rowscan be the same as a distance between adjacent depression columns ordifferent from a distance between adjacent depression columns. By way ofexample, FIG. 16 illustrates a substantially uniform distribution with aconstant distance between adjacent depression rows and between adjacentdepression columns.

In some exemplary embodiments, structure 200 includes a plurality offirst protrusions, such as first protrusion 230, and a plurality ofsecond protrusions, such as second protrusion 240. The plurality offirst protrusions and the plurality of second protrusions aremonolithically formed with the panel, protruding from the second panelwall toward an exterior of the panel. The first protrusions areelongated in the first direction, and the second protrusions areelongated in the second direction. In an exemplary embodiment, firstprotrusion 230 or second protrusion 240 has a tunnel shape or the like.

In some exemplary embodiments, first protrusions in at least a subset ofthe plurality of first protrusions are arranged alternatively withdepression rows in at least a subset of the plurality of depressionrows. Similarly, second protrusions in at least a subset of theplurality of second protrusions are arranged alternatively withdepression columns in at least a subset of the plurality of depressioncolumns. The first protrusions in the subset of the plurality of firstprotrusions and the second protrusions in the subset of the plurality ofsecond protrusions cross each other. Collectively, the firstdepressions, first protrusions, and second protrusions enhance astrength of the blow-molded unitary structure.

In some exemplary embodiments, a reinforcement member, such asreinforcement member 250, is monolithically formed at a first depressionin the plurality of first depressions. In an exemplary embodiment, thenumber of reinforcement members is the same as the number of firstdepressions, e.g., each first depression in the plurality of firstdepressions is formed with a reinforcement member. In another exemplaryembodiment, the number of reinforcement members is different from orless than the number of first depressions, e.g., one or more firstdepressions in the plurality of first depressions are not formed with areinforcement member. The reinforcement members further enhance thestrength of the structure.

Reinforcement member 250 can be formed at a side wall of the firstdepression or at the bottom of the first depression. In some exemplaryembodiments, the reinforcement member is formed at the bottom of thefirst depression and recessed further from the bottom of the firstdepression towards the first panel wall. In an exemplary embodiment, thereinforcement member forms a contact with the first panel wall.

Reinforcement member 250 can have any suitable regular or irregularshapes. In some exemplary embodiments, reinforcement member 250 includesa plurality of reinforcement elements, such as reinforcement element252. In an exemplary embodiment, the plurality of reinforcement elementsare connected with each other at their ends. For instance, by way ofexample, FIGS. 16 and 18 illustrate reinforcement member 250 havingthree reinforcement elements 252 connected with each other at their endsto form a three-pointed star shape.

First protrusion 230 and second protrusion 240 can have the same heightor different heights. For instance, in an exemplary embodiment, firstprotrusion 230 has a height substantially the same as second protrusion240. In another exemplary embodiment, first protrusion 230 has a heightgreater than second protrusion 240. In still another exemplaryembodiment, first protrusion 230 has a height less than secondprotrusion 240. The height of the first or second protrusion isgenerally measured from a peak of the first or second protrusion to thefirst panel, as illustrated by “h1” in FIG. 17.

In some exemplary embodiments, a height of a first or second protrusionis about 1/7 to about ⅘ of a distance between two adjacent firstdepressions, about ⅙ to about ¾ of a distance between two adjacent firstdepressions, or about ⅕ to about ⅔ of a distance between two adjacentfirst depressions. In an exemplary embodiment, the distance between twoadjacent first depressions is measured from a center of one firstdepression to a center of the other first depression, as illustrated by“d1” in FIG. 17. In FIG. 17, “d1” and “d2” indicate the distanceseparating adjacent first depressions in a row or column, respectively,measured from center-to-center of the adjacent depressions. “d5” and“d6” indicate the distance separating adjacent first depressions in arow or column, respectively, measured from edge-to-edge of the adjacentdepressions.

In some exemplary embodiments, a width of a first or second protrusionis about 1/7 to about ½ of a distance between two adjacent firstdepressions, about ⅙ to about ⅖ of a distance between two adjacent firstdepressions, or about ⅕ to about ⅓ of a distance between two adjacentfirst depressions. In an exemplary embodiment, the width of a first orsecond protrusion is measured from an edge of the first or secondprotrusion on the second panel to an opposite edge of the first orsecond protrusion on the second panel, as illustrated by “w” in FIG. 17.

In some exemplary embodiments, first depression 220 in the plurality ofdepression rows or in the plurality of depression columns is surroundedby a transition member, such as transition member 260. The transitionmember connects the first depression with adjacent first and secondprotrusions. In some exemplary embodiments, the transition memberincludes multiple steps. For instance, in an exemplary embodiment, thetransition member includes first step 261 and second step 262. Thesecond step is surrounded by the first step and recessed from the firststep toward the first panel wall.

In some exemplary embodiments, structure 200 includes additional,alternative or optional elements. For instance, in some exemplaryembodiments, structure 200 includes one or more second depressions, suchas second depression 270, monolithically formed with the panel tofurther enhance the strength of the structure. Like first depression220, second depression 270 recesses from the second panel wall towardthe interior of the panel. Unlike first depression 220, seconddepression 270 is generally curvy and disposed along one or more edgesof the panel. In some exemplary embodiments, the second depression has asubstantially wave shape, as illustrated in FIG. 16. In an exemplaryembodiment, the second depression is disposed along two, three or fouredges of the panel.

The depressions, protrusions, ribs, trenches, reinforcement members orthe like, or any combination thereof, enhance the strength of thestructure and thus prevent the structure from bending, warping ordeforming.

The terminology used herein is for the purpose of describing particularimplementations only and is not intended to be limiting of the claims.As used in the description of the implementations and the appendedclaims, the singular forms “a”, “an” and “the” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise. It will be understood that the terms “top” or “bottom”,“lower” or “upper”, and etc. are used to describe features of theexemplary embodiments with reference to the positions of such featuresas displayed in the figures. It will be understood that, although theterms “first,” “second,” etc. may be used herein to describe variouselements, these elements should not be limited by these terms. Theseterms are only used to distinguish one element from another. Forexample, a first panel wall could be termed a second panel wall, and,similarly, a second panel wall could be termed a first panel wall,without changing the meaning of the description, so long as alloccurrences of the “first panel wall” are renamed consistently and alloccurrences of the “second panel wall” are renamed consistently.

1-20. (canceled)
 21. A blow-molded unitary structure comprising: a panelcomprising a first panel wall and a second panel wall spaced apart fromthe first panel wall; a plurality of first depressions monolithicallyformed with the panel, each recessing from the second panel wall towardan interior of the panel; a plurality of first protrusionsmonolithically formed with the panel, each protruding from the secondpanel wall toward an exterior of the panel and elongated in the firstdirection; and a plurality of second protrusions monolithically formedwith the panel, each protruding from the second panel wall toward anexterior of the panel and elongated in the second direction; wherein: atleast a subset of the plurality of first depressions is arranged into aplurality of depression rows in a first direction and a plurality ofdepression columns in a second direction across at least a portion ofthe panel; first protrusions in at least a subset of the plurality offirst protrusions are arranged alternatively with depression rows in atleast a subset of the plurality of depression rows; second protrusionsin at least a subset of the plurality of second protrusions are arrangedalternatively with depression columns in at least a subset of theplurality of depression columns; the first protrusions in the subset ofthe plurality of first protrusions and the second protrusions in thesubset of the plurality of second protrusions cross each other; and theplurality of first depressions, the plurality of first protrusions, andthe plurality of second protrusions collectively enhance a strength ofthe blow-molded unitary structure.
 22. The blow-molded unitary structureof claim 21, further comprising: a plurality of reinforcement members,each monolithically formed at a first depression in the plurality offirst depressions.
 23. The blow-molded unitary structure of claim 22,wherein the number of reinforcement members is the same as the number offirst depressions, and one reinforcement is formed at each firstdepression in the plurality of first depressions.
 24. The blow-moldedunitary structure of claim 22, wherein each reinforcement member in theplurality of reinforcement members is formed at a depression bottom of acorresponding first depression in the plurality of first depressions.25. The blow-molded unitary structure of claim 24, wherein eachreinforcement member in the plurality of reinforcement members isrecessed from the depression bottom of the corresponding firstdepression in the plurality of first depressions towards the first panelwall.
 26. The blow-molded unitary structure of claim 24, wherein thereinforcement member comprises a plurality of reinforcement elementsconnected with each other at ends thereof.
 27. The blow-molded unitarystructure of claim 21, wherein a first protrusion in the plurality offirst protrusions and a second protrusion in the plurality of secondprotrusions have different heights.
 28. The blow-molded unitarystructure of claim 21, wherein a height of a first protrusion in theplurality of first protrusions or a second protrusion in the pluralityof second protrusions is about 1/7 to about ⅘ of a distance between twoadjacent first depressions, about ⅙ to about ¾ of the distance betweentwo adjacent first depressions, or about ⅕ to about ⅔ of the distancebetween two adjacent first depressions.
 29. The blow-molded unitarystructure of claim 28, wherein the distance between two adjacent firstdepressions is measured from a center of one first depression to acenter of the other first depression.
 30. The blow-molded unitarystructure of claim 21, wherein a width of a first protrusion in theplurality of first protrusions or a second protrusion in the pluralityof second protrusions is about 1/7 to about ½ of a distance between twoadjacent first depressions, about ⅙ to about ⅖ of the distance betweentwo adjacent first depressions, or about ⅕ to about ⅓ of the distancebetween two adjacent first depressions.
 31. The blow-molded unitarystructure of claim 30, wherein the distance between two adjacent firstdepressions is measured from a center of one first depression to acenter of the other first depression.
 32. The blow-molded unitarystructure of claim 21, wherein a first depression in the plurality ofdepression rows or in the plurality of depression columns is surroundedby a transition member that connects the first depression with adjacentfirst and second protrusions.
 33. The blow-molded unitary structure ofclaim 32, wherein the transition member comprises a first step and asecond step.
 34. The blow-molded unitary structure of claim 21, furthercomprising: a second depression monolithically formed with the panel andrecessing from the second panel wall toward the interior of the panel,wherein the second depression is curvy and disposed along one or moreedges of the panel.
 35. The blow-molded unitary structure of claim 34,wherein the second depression has a substantially wave shape.
 36. Theblow-molded unitary structure of claim 21, wherein a first protrusion inthe plurality of first protrusions or a second protrusion in theplurality of second protrusion has a tunnel shape.
 37. A blow-moldedunitary structure comprising: a panel comprising a first panel wall anda second panel wall spaced apart from the first panel wall; a pluralityof first depressions monolithically formed with the panel, eachrecessing from the second panel wall toward an interior of the panel,wherein at least a subset of the plurality of first depressions isarranged into a plurality of depression rows in a first direction and aplurality of depression columns in a second direction across at least aportion of the panel; and a second depression monolithically formed withthe panel and recessing from the second panel wall toward the interiorof the panel, wherein the second depression is curvy and disposed alongone or more edges of the panel.
 38. The blow-molded unitary structure ofclaim 37, wherein the second depression has a substantially wave shape.39. The blow-molded unitary structure of claim 37, wherein the seconddepression is disposed along two, three or four edges of the panel. 40.The blow-molded unitary structure of claim 37, further comprising: aplurality of reinforcement members, each monolithically formed at afirst depression in the plurality of first depressions.
 41. Theblow-molded unitary structure of claim 40, wherein the number ofreinforcement members is the same as the number of first depressions,and one reinforcement is formed at each first depression in theplurality of first depressions.
 42. The blow-molded unitary structure ofclaim 37, wherein each reinforcement member in the plurality ofreinforcement members is formed at a depression bottom of acorresponding first depression in the plurality of first depressions.43. The blow-molded unitary structure of claim 42, wherein eachreinforcement member in the plurality of reinforcement members isrecessed from the depression bottom of the corresponding firstdepression in the plurality of first depressions towards the first panelwall.
 44. The blow-molded unitary structure of claim 37, wherein thereinforcement member comprises a plurality of reinforcement elementsconnected with each other at ends thereof.
 45. The blow-molded unitarystructure of claim 37, wherein a first depression in the plurality ofdepression rows or in the plurality of depression columns is surroundedby a transition member that connects the first depression with one ormore adjacent protrusions, wherein the transition member comprises afirst step and a second step.
 46. A blow-molded unitary structurecomprising: a panel comprising a first panel wall and a second panelwall spaced apart from the first panel wall; a plurality of firstdepressions monolithically formed with the panel, each recessing fromthe second panel wall toward an interior of the panel, wherein at leasta subset of the plurality of first depressions is arranged into aplurality of depression rows in a first direction and a plurality ofdepression columns in a second direction across at least a portion ofthe panel; and a plurality of reinforcement members, each monolithicallyformed at a first depression in the plurality of first depressions,wherein each reinforcement member in the plurality of reinforcementmembers is formed at a depression bottom of a corresponding firstdepression in the plurality of first depressions.
 47. The blow-moldedunitary structure of claim 46, wherein the number of reinforcementmembers is the same as the number of first depressions, and onereinforcement is formed at each first depression in the plurality offirst depressions.
 48. The blow-molded unitary structure of claim 46,wherein each reinforcement member in the plurality of reinforcementmembers is recessed from the depression bottom of the correspondingfirst depression in the plurality of first depressions towards the firstpanel wall.
 49. The blow-molded unitary structure of claim 46, whereinthe reinforcement member comprises a plurality of reinforcement elementsconnected with each other at ends thereof.
 50. The blow-molded unitarystructure of claim 46, wherein a first depression in the plurality ofdepression rows or in the plurality of depression columns is surroundedby a transition member that connects the first depression with one ormore adjacent protrusions, wherein the transition member comprises afirst step and a second step.